nixpkgs/nixos/modules/tasks/encrypted-devices.nix
André-Patrick Bubel 2000fba561
nixos/fileystems: Fix boot fails with encrypted fs
Boot fails when a keyfile is configured for all encrypted filesystems
and no other luks devices are configured. This is because luks support is only
enabled in the initrd, when boot.initrd.luks.devices has entries. When a
fileystem has a keyfile configured though, it is setup by a custom
command, not by boot.initrd.luks.

This commit adds an internal config flag to enable luks support in the
initrd file, even if there are no luks devices configured.
2017-09-14 05:27:41 +02:00

72 lines
2.1 KiB
Nix

{ config, lib, ... }:
with lib;
let
fileSystems = config.system.build.fileSystems ++ config.swapDevices;
encDevs = filter (dev: dev.encrypted.enable) fileSystems;
keyedEncDevs = filter (dev: dev.encrypted.keyFile != null) encDevs;
keylessEncDevs = filter (dev: dev.encrypted.keyFile == null) encDevs;
isIn = needle: haystack: filter (p: p == needle) haystack != [];
anyEncrypted =
fold (j: v: v || j.encrypted.enable) false encDevs;
encryptedFSOptions = {
encrypted = {
enable = mkOption {
default = false;
type = types.bool;
description = "The block device is backed by an encrypted one, adds this device as a initrd luks entry.";
};
blkDev = mkOption {
default = null;
example = "/dev/sda1";
type = types.nullOr types.str;
description = "Location of the backing encrypted device.";
};
label = mkOption {
default = null;
example = "rootfs";
type = types.nullOr types.str;
description = "Label of the unlocked encrypted device. Set <literal>fileSystems.&lt;name?&gt;.device</literal> to <literal>/dev/mapper/&lt;label&gt;</literal> to mount the unlocked device.";
};
keyFile = mkOption {
default = null;
example = "/root/.swapkey";
type = types.nullOr types.str;
description = "File system location of keyfile. This unlocks the drive after the root has been mounted to <literal>/mnt-root</literal>.";
};
};
};
in
{
options = {
fileSystems = mkOption {
options = [encryptedFSOptions];
};
swapDevices = mkOption {
options = [encryptedFSOptions];
};
};
config = mkIf anyEncrypted {
boot.initrd = {
luks = {
devices =
map (dev: { name = dev.encrypted.label; device = dev.encrypted.blkDev; } ) keylessEncDevs;
cryptoModules = [ "aes" "sha256" "sha1" "xts" ];
forceLuksSupportInInitrd = true;
};
postMountCommands =
concatMapStrings (dev: "cryptsetup luksOpen --key-file ${dev.encrypted.keyFile} ${dev.encrypted.blkDev} ${dev.encrypted.label};\n") keyedEncDevs;
};
};
}